Method and apparatus for extrusive rolling of non-cylindrical hollow bodies



Dec. 14, 1965 A. w. ERNESTUS 3,222,904

METHOD AND APPARATUS FOR EXTRUSIVE ROLLING OF NON-CYLINDRICAL HOLLOW BODIES Filed May 14, 1962 4 Sheets-Sheet 1 IN V EN TOR. 1400M WEAA/EJH/J Arman/5y Dec. 14, 1965 A. w. ERNESTUS 3,222,904

METHOD AND APPARATUS FOR EXTRUSIVE ROLLING OF NON-CYLINDRICAL HOLLOW BODIES 4 Sheets-Sheet 2 Filed May 14, 1962 INVENTOR 400m WEwvwn/s BY g g firm/m5) Dec. 14, 1965 A. w. ERNESTUS 3,222,904

METHOD AND APPARATUS FOR EXTRUSIVE ROLLING OF NON-CYLINDRICAL HOLLOW BODIES Filed May 14, 1962 4 Sheets-Sheet I5 INVENTOR. ADOLPH fl/Ewvmrw A'rm/am/Er I Dec. 14. 1965 A. w. ERNESTUs 3,222,904 METHOD AND APPARATUS FOR EXTRUSIVE ROLLING OF NON-CYLINDRICAL HOLLOW BODIES Filed May 14, 1962 4 Sheets-Sheet 4 [/5 r Ii MW 111A 4- if z I g 0% //2, V

\ Z1 INVENTOR,

100m 14. fk/vfs m5 BY United States Patent 3,222,904 METHOD AND APPARATUS FOR EXTRUSIVE RQLLING 0F NON-CYLINDRICAL HOLLOW BODIES Adolph W. Ernestus, Los Angeles, Calif., assignor to N.T.W. Missile Engineering, Inc., Los Angeles, Calif., a corporation of California Filed May 14, 1962, Ser. No. 194,301 Claims. (Cl. 72-91) This invention relates to metal-spinning or roll-forming in general, and in particular to the forming of largedimension hollow articles of circular cross section but non-cylindrical form (e.g. conical or conoidal). The general object of the invention is to provide a method and apparatus for forming articles of this kind with a high degree of accuracy in maintaining a predetermined configuration.

In a specific aspect, the invention relates to the forming of relatively thin-wall articles of a metal having a high heat resistivity and a correspondingly low degree of ductility, such as the metals in the titanium group for which there is an increasing demand in the fabrication of nose cones for missiles and space vehicles required to withstand extremely high temperatures upon re-entry into atmosphere from outer space, and which have a considerably higher degree of brittleness than the commoner, less heat-resistant metals such as the bronzes and stainless steels, and are correspondingly more difficult to control in forming and spinning operations and are more subject to Warping and fissuring during forming operations.

A further object is to provide a method and apparatus for forming such articles without wasting material, since the rare metals herein contemplated are extremely expensive.

With the foregoing in mind, the invention contemplates a method and apparatus for internally roll-forming a relatively thick-wall blank of relatively short axial dimension into a relatively thin-wall article which has been increased in axial length several times over that of the initial work blank.

A further object is to provide such a method of rollforming an article wherein the external contour and finish of the article is accurately determined by the internal wall contour of a die within which the work blank is supported and against which it is rolled and extended axially in the forming operation.

A further object is to provide an improved apparatus for effecting such a roll-forming operation, including a female forming die having means for rotating the same on its major axis, and a rolling head having means for positioning the same in successive positions of adjustment in a generally axial direction paralleling the contour of the internal wall of the die in a plane of its major axis.

Another object is to provide an improved method and apparatus for extrusive roll-forming of relatively thick, short annular blanks of various metals of varying degrees of ductility, into very thin-walled, axially elongated articles of circular cross section, with an extremely high degree of conformity to external wall configuration and finish requirements. For example, I find that the invention can be utilized to fulfill a demand which is currently developing for a hollow article (e.g. fuel container) liner or skin of a suitably corrosion-resistant metal such as aluminum having a wall of paper thinness, e.g., as thin as .030".

Other objects and advantage will become apparent-in the ensuing specification and appended drawing in which:

FIG. 1 is a perspective view of a roll-forming apparatus embodying my invention;

3,222,904 Patented Dec. 14, 1965 FIG. 2 is a side elevational view of a work blank, partly in axial section, in its original dimensional form;

FIG. 3 is a side elevational view, partially in axial section, of a finished work article deveoped from the blank of FIG. 2;

FIG. 3a is a side elevational view of a finished Work article of a modified form, likewise developed from the blank of FIG. 2;

FIG. 4 is a vertical axial sectional view of the apparatus with the rolling head actuator shown in side elevation;

FIG. 5 is a fragmentary plan view of the same;

FIG. 6 is a horizontal cross-sectional view of the same taken on the line 66 of FIG. 4;

FIG. 7 is a horizontal sectional view of the same taken on the line 7-7 of FIG. 4;

FIG. 8 is a side elevational view of the apparatus as seen within the die which is shown in axial section; looking forwardly as indicated by line 88 of FIG. 6;

FIG. 9 is a side elevational view of the forming roller and guide and holder units of the internal assembly;

FIG. 10 is a vertical sectional view taken in an inclined transverse plane looking outwardly as indicated by line 1010 of FIG. 9;

FIG. 11 is a vertical transverse sectional view taken in substantially the same plane as FIG. 10 but looking inwardly as indicated by line 1111;

General description Referring now to the drawings in detail, particularly FIGS. 1-11, I have shown therein, as an example of a means successfully operative in performing the method of my invention, an apparatus including, in general, a power driven turntable A; a gantry frame B bridging over the turntable A; a carriage C mounted for vertical travel in gantry frame B; a female forming die D mounted on turntable A; an actuator E for transmitting horizontal movement to the carriage C; a forming roller unit F for rolling operation against the internal Wall of the work blank W; a guide G in which the forming unit F is mounted for generally vertical adjustments along a path paralleling the vertical cross sectional internal contour of die D; a holder H in which the guide G is mounted for generally horizontal adjustments radially of the work axis (of rotary movement of the die D) for moving the rolling unit F into indenting relation to the inner wall of the work blank W; an actuator I for transmitting vertical adjusting movements to the forming unit F along the path guided by the guide G; and an adjustment unit I for effecting the horizontal adjustments of the forming unit F with respect to the major operational axis X.

Detailed description Turntable A.-May be of a conventional construction such as is utilized in vertical boring mills, suitablymounted in a floor pit 20 and rotated by power drive means (which can be conventional and is therefore not illustrated) located below the floor level. Mounted upon the turntable A at its center is a suitable base 21 having an upstanding mounting collar 22 to which the die D is mounted.

Gantry Frame B.Comprises vertical legs 25 connected at their upper ends by a bridging beam 26, the legs 25 comprising spaced parallel vertical ways in which the respective ends of carriage C are mounted for vertically sliding adjustments provided for by power driven jack screws 27. These parts likewise may be of conventional construction and their construction and arrangement well known, and consequently are not illustrated in detail herein.

spective ends, shoes 30 provided with conventional vertically slidable connections with the ways of legs 25; a pair of vertically spaced horizontal ways 31 bridging between and supported by the shoes 30; and a bracket 32 secured to the ways 31 and mounting the horizontal actuator E. The ways.31 slidingly support a horizontally movable carriage portion of holder H.

Forming Die D.(FIG. 4) comprises a bowl 35 having a base flange 36 adapted to be bolted down upon the base collar 22 by tie-bolts 37 which extend through the flange 36 and the collar 22 and are anchored in the base 21. For accurate centering of the bowl, it is provided with a bottom lip 38 which is piloted in a counterbore 39 in the collar 22.

Bowl 35 has a highly polished internal forming wall 40 of a selected contour which in most cases will depart from a cylindrical configuration. It is to be understood that the invention can be employed in the forming of cylindrical articles within a cylindrical die, although its chief advantage is in the forming of double-curved, generally conical surfaces, the wall 40 as shown being conoidal, and suitable for the major section of the nose cone of a missile.

Bowl 35 has a rim provided with a cylindrical counterbore 41 which functions as a radial guide bearing surface as will be explained more fully hereinafter. The rim of the bowlis reinforced by a hoop or band 42 resisting expansion of the die under the extremely high radial loads imposed upon it by the forming operation.

The lower end of the die is open. The opening therein may be defined by a cylindrical wall 43 for receiving, with a piloting action, a cylindrical anchor collar 44 at one end of the work W.

The work blank, in its original form, embodies a relatively thick and axially short wall section 45-shaped with a flare conforming generally to the contour of internal wall 40 of dieD at the base thereof, as indicated in FIG. 4. In the neck 44 is an annular internal groove 46. Work blank W is securely anchored in the die by a circumferential array of segmental-circular clamp jaws 47 ofZ-shape in cross-section, each having a bottom flange 48 secured to turntable 21 by a number of screws 49 extending through circumferentially-spaced apertures therein. and threaded into the turntable, and each having atop flange projecting radially outwardly and engaged in thel annular groove 46 of neck 44.

Actuator 'E.'-(FIG. 1), comprises a cylinder 50 anchored to bracket 32, a piston (not shown) operating in the cylinder, connections at respective ends of the cylinder to hydraulic lines 51 and 52, and a piston rod 53 attached to the piston, extending through a conventional packing gland in one of the two closed ends of the cylinder, and anchored in an adjacent side of holder H. Actuator E is operable to shift the holder H from the position shown in FIG. 1, centered abovethe die D, horizontally to a position offset to one side of die D (the side remote from the observer in FIG. 1), for servicing.

Forming Roller Unit F.(FIGS. 4, 7 and comprises a slide in the form of a rectangular box frame having laterally "spaced side members 55 joining transverse members 56 at the upper and lower extremities of the frame and framing a rectangular central aperture in which is disposed the forming roller 57. The slide further. includes four follower rollers 58 disposed at the four corners of the slide frame, on transverse axes, a pair at each side, top and bottom, and journalled on the respective ends of axles '59 extending through transverse bores in the transverse frame members 56. Follower rollers 58 are guided in ways in guide G. The slide further includes four lateral positioning rollers 60, journalled on stub shafts which are anchored in the back side of the slide frame, at the four corners thereof, projecting rearwardly.

Forming roller 57 is rotatably mounted on a heavy upright shaft 61 the respective ends of which are mounted in alig e semi-cylindrical saddle seats 62 in transver e frame members 56 and clamped therein by transverse arched clamps 63 (FIGS. 4 and 6). Roller 57 is mounted to turn freely on a needle bearing 64 interposed between it and the shaft 61. Heavy end loads imposed on roller 57 by the reaction of metal being extruded axially along the inner wall of the work W, are absorbed by end bearings 65 which are engaged between the ends of the roller 57 and seats in the inward faces of transverse frame members 56.

Rollers 58 (FIG. 6) are mounted for free rolling on roller bearings 66 on the ends of shafts 59, and are retained thereon by retainer nuts 67 threaded onto the ends of the shafts.

Guide G.--(FIGS. 4, 6, 7, 9 and 10) comprises a pair of laterally opposed, spaced roller guides 70 defining ways 71 of arcuate longitudinal contour paralleling the crosssectional contour of the inner wall 40 of die D in a plane (vertical) of the major axis X of revolution of the die. The follower rollers 58 (of a diameter slightly smaller than the transverse width of ways 71) are disposed in the ways 71, and make load-bearing rolling contact with the rear walls of the respective ways when in extrusive rolling contact with the work W. Such rear walls are defined by the forward faces of heavy ramp bars 72. The arcuate contour of these forward faces of ramp bars 72 determines the path of a series of extrusive feed passes executed by the roller, moving from a lower limit position where it contacts the work W adjacent the groove 46, to an upper limit position at the upper end of the work.

The lateral positioning rollers 60 roll against fiat parallel inward faces of the ramp bars 72, centering the forming unit F between the ways 71 and preventing dragging of the ends of shafts 59 against the bottoms of ways 71.

Ramp bars 72 have straight flat ramps 73 defining their rear margins, facing toward the transverse plane of axis X and diverging from said plane in an upward direction roughly parallel to ways 71. Ramps 73 are acted upon by adjustment unit I.

Roller guides 70 are secured to outer faces of ramp bars 72 as shown. Ramp bars 72 are secured to respective pairs of vertically spaced horizontal slide shoes 74 (FIGS. 7 and 10) which are slidably supported by the holder H.

Holder H .(FIGS. 1, 4, 611) comprises, at its lower end, a slideway cage (FIG. 7) comprising laterally spaced parallel slide plates 76 having, in their inward faces, slideways 75 in which the slide shoes 74 are slidable for adjustment of guide G radially of major axis X. Slideway plates 76 are secured by bolts 77 to respective laterally spaced vertical members 78 of an H-frame having cross members 79 and laterally spaced vertical front members 80. Cross members 79 are provided with semicircular central notches in their forward sides, and are welded to the rear surface of a cylindrical hub 84 along the margins of the notches. The inner margins of front members 80 likewise are welded to the respective sides of hub 84. At their upper ends, side member 78 and front members 80 are welded to the under face of the lower of a pair of horizontal plates comprising a positioning head 81.

Head 81 carries a circumferential array of centering rollers 82 mounted to its periphery in U-brackets 83. A hub 84, integral with head 81, projects vertically through its center, and has an axial bore through which is extended a pilot shaft 85. The lower end of shaft 85 is threaded into a central bore in turntable 21 and thus: anchored thereto in an upstanding position. A conical. assembly 86 of roller bearings is mounted on a reduced neck 87 on the lower end of hub 84, and is received in a retainer cup 88 in the center of turntable 21. When the holder is being lowered into the die, the bearing assembly 86 is guided into the cup 88 by pilot shaft 85. When thus coupled to the turntable, holder H is secured by a nut 89 threaded OIJIQ the UPI e d of shaft 3 abutting an end thrust bearing 90 seated in a counterbore in the upper end of hub 84 and absorbing the upward thrust reaction loads imposed on the holder H by the extrusive rolling operations.

At its upper end, holder H has a pair of laterally projecting slide wings 91 which are slidably mounted to the ways 31 of carriage C by slide shoes 92. Wings 91 are formed as integral projections on the upper end of hub 84.

Holder H further includes a pair of arms 93 formed integrally with respective sides of hub 84 at the upper end thereof, projecting upwardly in laterally spaced, parallel relation, and having, at their upper ends, forwardly projecting fingers 94 supporting a transverse pintle 95 on which actuator I is suspended.

Actuator I.Comprises a cylinder 100 having its upper end closed by a cap provided with a lug 101 which is pivotally linked to the pintle 95, and its lower end closed by a gland cap 102. A piston 103, slidable in the cylinder 100, has a piston rod 104 extending through and sealed in cap 102. Hydraulic lines 105 and 106 are connected to the upper and lower ends of the cylinder 100, for two-way power actuation of piston 103. The lower end of piston rod 104 is anchored to a clevis 107 which is pivotally coupled to the upper follower roller shaft 59, for push-pull actuation of forming roller unit F in the arcuate extrusion path determined by the travel of follower rollers 58 in ways 70. The parallel arms of clevis 107 (FIG. 6) are received in slots 108 in upper slide frame member 56.

Adjustment Unit J.(FIGS. 4, 6, 7, 9 and 11) comprises a pair of wedges 110 disposed immediately rearwardly of ramp bars 72 and in common planes therewith, vertically spaced cross-arches 111 and 112 secured to and bracing the wedges 110 in their laterally spaced relationship, the arches 111, 112 having, in their rear sides, semicircular recesses receiving the semicylindrical forward surface of hub 84; an adjustment screw 113 having a shank 114 rotatably mounted in a vertical central bore in cross-arch 111 and having end thrust bearings 115 and 116 held between a collar 117 secured on shank 114, and an integral head'118 on shank 114; and a nut 119 which is anchored in hub 84 (FIGS. 4 and 7) by bolts 120. The rear sides of wedges 110 are vertical and are in sliding bearing engagement with the forward faces of vertical bearing members 80 of the H-frame of holder H. They are retained in such sliding engagement by threaded stud assemblies 121 which extend through vertical slots 122 (FIG. 8) in the vertical members 80.

It will now be apparent that by applying a wrench to the squared tip of head 118 and rotating the screw 113 in a forward direction, the screw will draw the arch 111 downwardly, in a vertical path, thus forcing the wedges 110 downwardly against the ramp surfaces 73 of ramp bars 72 so as to move the roller 57 outwardly from work axis X, such outward movement being guided by sliding of shoes 74 in slide Ways 75 of the slideway plate 76 of holder H.

The method In preparation for extrusive rolling of an article using the process of my invention, as carried out by the ap paratus shown, the elevator screw jacks 27 are operated to elevate the carriage C to the heighth shown in FIG. 1, in which the lower extremity of the units F, G and H will clear the top of the die D. The horizontal actuator E is then operated to shift the holder H (and the units F, G and I carried thereby) to a position at one side of the die D so that the top of the die is exposed. A work blank W is then lowered into the die and a workman then enters the die and attaches the clamping segments 47 to the anchor collar 43 of the work blank W, draw ing the Work blank snugly downwardly into tight engagement with the lower zone of the inner wall 40 of the die.

In the removal of the holder and its associated units from the die, the nut 89 has been removed from the upper end of shaft and the holder is slid upwardly over the shaft, leaving the latter upstanding in the turntable 21. When the work blank W has been scurely fastened in the die, the horizontal actuator E is operated to move the holder back to a position centered above the die and the screw jacks 27 are then carefully operated to lower the carriage C until the bore in the lower end of the holder neck 87 is in position to receive the upper end of shaft 85, the actuator B being operated further to obtain exact registration between the bore and the shaft, if necessary. The carriage is then lowered to the lower limit position, the holder hub 84 sliding downwardly over the shaft 85 until its bearing assembly 86 comes to rest within the bearing cup 88 of the turntable. The nut 89 is then threaded onto the upper end of the shaft 85 and tightened against the bearing 90, securing the holder and its associated units against upward movement in the subsequent operation of the apparatus.

Before inserting the holder and the units F and G into the die, the adjustment units I are operated to retract the roller 57 toward the major work axis X, to an inner limit position where it will clear the inner wall of the Work blank W. The stroking actuator I is then operated to lower the roller unit F to the position shown in broken lines in FIG. 4, wherein the roller is centered in engagement with the inner wall of the work blank W just above the clamping groove 46, and with pressure contact established with the inner wall of the work, just sufiicient to start the rolling operation when the die is rotated. The turntable is then operated to rotate the die, and the adjustment unit I is operated to gradually move the roller 57 radially outwardly so as to roll an annular groove in the wall of the work blank adjacent groove 46 while the rolling unit F remains at a fixed level. This state of operation is terminated when the groove is developed to a pre-selected depth below the surface of the inner wall of the Work blank. The roller is then left at its then existing radial position with respect to the follower groove 71, and the stroking actuator I is then operated to gradually draw the unit F upwardly, following the extrusion path determined by the engagement of roller 58 against the inner wall of groove 71 until one rolling pass, to the top of the blank W, has been completed. During the pass, the thickness of the wall 45 of the work will be reduced to an extent equal to the depth of which the roller has been indented below the original inner surface of wall 45, and excess metal will be extruded upwardly along the inner surface of the blank, elongating the wall 45 to an added percentage of heighth. The upward pass is continued until the roller is centered at the upper extremity of the elongated wall of the work, and the actuator I is then reversed and operated to effect a relaing this return, the radial position of roller 57 with tively quick return of the roller to its starting level. Durrespect to follower groove 71 is held unchanged. A cycle of operation is then commenced in which the stroking actuator I is held inactive to hold the roller at the starting depth while the adjustment unit I is slowly adjusted to move the roller 57 radially outwardly to roll another annular groove in the work adjacent the anchor collar 43 to a selected depth (which may be the same, or slightly less than the depth to which the first annular groove was rolled). The operation of adjustment unit I is then arrested, causing the roller 57 to be held at this new radial position, while the stroking actuator I is op erated to move the roller 57 slowly upwardly in a second pass in which it is held at a constant depth of indentation into the inner wall of the work blank W, extruding metal upwardly and again elongating the blank.

Successive cycles of similar operation are carried out, with the work blank being successively reduced to thinner wall dimension and greater heights, until finally a completed work article W, shown in FIG. 3 is developed.

The mod ified work article-FIG. 30 may be developed by a similar operation (utilizing a roller with less rounded corners and more nearly cylindrical form), the process being varied by utilizing a series of relatively short upward passes of the rolling unit F instead of the full heighth continuous pass described above. These short passes are utilized to develop respective successive zones of thinning of the wall structure of the blank, with relatively narrow intervening zones where the blank remains unthinned, thus developing relatively thick rein-forcing ribs 45a between the successive thinned wall sections 45b.

I claim:

1. An extrusive rolling method of forming a thinwalled hollow metal article of flaring wall configuration, including the following steps: fitting and securing a relatively thick short work blank is a female die having an internal wall configuration of circular cross-section and flaring at an angle of less than 45 to the axis of generation, conforming to the required external wall shape of the finished article; applying a forming roller under radially outward pressure in indenting contact with the inner wall of the work; effecting relative rotation about said axis between said forming roller and the die and work blank and simultaneously moving said roller slowly from the smaller to the larger end of the work in a series of passes of the roller in a generally axial direction, in a path diverging from said axis of generation at an angle of less than 45 and corresponding to the cross-sectional contour, in an axial plane, of the inner wall of the article, while holding the smaller end of the work securely anchored to the die in fixed relation thereto and applying radially outward thrust to said roller to effect extrusive rolling action, and thereby extruding metal axially so as to elongate the Work While reducing its wall thickness; utilizing rolling contact with the inner wall of the die to absorb the reaction to said thrust; returning the roller relatively rapidly from the outer end to the inner end of the work in non-extrusive contact therewith at the end of each pass; and adjusting the roller radially outwardly at the beginning of the next succeeding pass so that said path of roller movement successively approaches more closely to an finally coincides exactly with said internal wall cross-sectional contour.

2. Extrusive rolling apparatus comprising: a female forming die having an inner wall flaring toward an open large end; means holding the die and rotating it; a roller unit including a slide and a forming roller journalled therein on an axis generally parallel to the cross-sectional contour of said inner wall in a plane of the axis of rotation; a guide in which said slide is guided for movement in an extrusion path parallel to said cross-sectional contour; a holder in which said guide is mounted for adjustment generally radially of the axis of die rotation, a power-operated actuator for moving said roller slide along said extrusion path; and means for adjusting said guide radially to adjust said roller closer to said inner wall of the die for reducing the wall thickness of the work.

3. Apparatus as defined in claim 2, wherein said holder is provided with reaction thrust rollers for hearing against the inner wall of the rim of the die and providing a fulcrum from which the radial thrust of said forming roller is delivered.

4. Apparatus as defined in claim 2, including means supporting said holder and actuator for insertion into and withdrawal from the die.

5. Extrusive rolling apparatus comprising: a female forming die having an inner wall flaring toward an open large end; means holding the smaller end of the die and rotating it; a forming roller; means supporting said roller for rotation and for translational movement in an extrusion path parallel to the cross-sectional contour of said inner wall in a plane of the axis of rotation of the die; a ower operated actuator for moving said roller in said ex trusion path; and means acting between said roller and said supporting means for adjustment of said roller radially with reference to said axis to bring it closer to said inner wall of the die for reducing the wall thickness of the work; and a reaction thrust roller carried by said holder and bearing against the die wall in radial opposition to the thrust of said forming roller and providing a fulcrum for application of said thrust.

6. In an extrusive rolling apparatus, in combination: a rotary turntable; a forming die having an internal wall of conoidal form, secured to said turntable for rotation on its major axis on which said conoidal form is developed; means for securing in the bottom of said die a work blank of relatively thick-walled, axially short dimensions, fitted to said internal die wall; a forming roller; a slide in which said roller is journalled; a guide comprising laterally opposed ways of arcuate longitudinal configuration corresponding to the cross-sectional contour of said internal die wall in a plane of said major axis, said slide having laterally opposed follower means travelling in said ways so as to guide said forming roller in an extrusion path conformed to said cross-sectional contour; a holder having transverse ways in which said guide is mounted for adjustment radially with reference to said major axis; adjustment means acting between said holder and said guide, for effecting said radial adjustment, said holder including a hub having at one end thereof, pilot bearing means for coupling connection to the center of said turntable, for locating said holder coaxial with said die, and including circumferentially spaced reaction thrust rollers positioned in opposed relation to said forming roller across said major axis, for bearing against an internal bearing wall at the rim of said die; a carriage on which said holder is mounted for translational movements toward and from the die; and an actuator mounted on said carriage and acting between said carriage and said slide for moving said slide in said extrusion path.

7. Apparatus as defined in claim 6, wherein said major axis is vertical, said turntable is horizontal, said die pro-- jects upwardly from said turntable, and said carriage includes horizontal ways in which said holder is mounted for traverse transversely of said major axis; and further including an actuator operating between said carriage and holder for effecting said traverse, and a gantry frame in which said carriage is mounted for elevating and lowering movements to withdraw and insert said holder and forming roller from and into said die.

8. In an extrusive rolling apparatus, in combination: a rotary drive member; a forming die having an internal wall of conoidal form, secured to said drive member for rotation on its major axis on which said conoidal form is developed; means for securing in the bottom of said die a work blank of relatively thick-walled, axially short dimensions, fitted to said internal die wall; a forming roller; a slide in which said roller is journalled; a guide comprising laterally opposed ways of arcuate longitudinal configuration corresponding to the cross-sectional contour of said internal die wall in a plane of said major axis, said slide having laterally opposed follower means travelling in said ways so as to guide said forming roller in an ex trusion path conformed to said cross-sectional contour; a holder having transverse ways in which said guide is mounted for adjustment radially with reference to said major axis; adjustment means acting between said holder and said guide, for effecting said radial adjustment, said ad ustment means comprising a wedge interposed between said holder and said guide and longitudinally movable therebetween for effecting a spreading action in which said guide is projected transversely of said holder; and an actuator screw acting between said wedge and said holder to effect said longitudinal movement of the wedge.

9. Apparatus as defined in claim 8, wherein said holder comprises a hub journalled in the bottom of said die and rising therefrom on the axis thereof, and reaction thrust bearing means disposed in diametrically-opposed relation to said forming roller and having rolling engagement against the inner wall of said die near its periphery, said wedge embodying a pair of laterally spaced ramp arms embracing said hub, and a bridge joining said bars at one end, an actuator screw extending through said bridge and rotatable therein, an end thrust bearing acting between said screw and said bridge, and a nut anchored to the side of said hub, said screw being threaded through said nut and operable to draw said ramp arms longitudinally between said holder and said guide, the latter having on the rear margins of said ways, ramp faces against which said ramp arms are slidably engaged, said wedge being fulcrumed against said holder hub for sliding movement parallel to said major axis.

10. Extrusive rolling apparatus comprising: a female forming die having an inner wall flaring toward an open large end at an angle of less than 45 to the axis of generation thereof; a forming unit including a forming roller and means in which said roller is journalled; means supporting said forming unit and said die for relative rotation upon a work axis coaxial with said inner wall, the rolling axis of said roller being disposed in a plane of said axis of relative rotation; guide means for directing said roller unit in a series of passes of said roller parallel to said inner wall; a holder carrying said guide means and said forming unit; said holder including a hub having its lower end journalled in the bottom of said die and having an arm projecting radially therefrom in a plane near the upper end of the die in diametrically opposed relation to said forming roller and having a thrust reaction roller bearing against the inner wall of the die adjacent said upper end thereof; a stroking actuator operating between said holder and said forming unit for stroking the latter in said series of passes; and means for adjusting said roller to successively narrower spacing with respect to said inner wall of the die whereby to successively reduce said blank to thinner wall structure while extruding it outwardly toward said open end of the die.

References Cited by the Examiner UNITED STATES PATENTS 601,566 3/ L893 Huston 1l352 603,094 4/ 1898 Worth 113-52 689,688 12/ 1901 Nodder 80-13 1,528,832 3/1932 Kellogg 8013 FOREIGN PATENTS 105,313 l/ 1927 Austria.

OTHER REFERENCES Platzer: German applicationP 7713, May 17, 1956.

CHARLES W. LANHAM, Primary Examiner. WILLIAM J. STEPHENSON, Examiner. 

2. EXTRUSIVE ROLLING APPARATUS COMPRISING: A FEMALE FORMING DIE HAVING AN INNER WALL FLARING TOWARD AN OPEN LARGE END; MEANS HOLDING THE DIE AND ROTATING IT; A ROLLER UNIT INCLUDING A SLIDE AND A FORMING ROLLER JOURNALLED THEREIN ON AN AXIS GENERALLY PARALLEL TO THE CROSS-SECTIONAL CONTOUR OF SAID INNER WALL IN A PLANE OF THE AXIS OF ROTATION; A GUIDE IN WHICH SAID SLIDE IS GUIDED FOR MOVEMENT IN AN EXTRUSION PATH PARALLEL TO SAID CROSS-SECTIONAL CONTOUR; A HOLDER IN WHICH SAID GUIDE IS MOUNTED FOR ADJUSTMENT GENERALLY RADIALLY OF THE AXIS OF DIE ROTATION, A POWER-OPERATED ACTUATOR FOR MOVING SAID ROLLER SLIDE ALONG SAID EXTRUSION PATH; AND MEANS FOR ADJUSTING SAID GUIDE RADIALLY TO ADJUST SAID ROLLER CLOSER TO SAID INNER WALL OF THE DIE FOR REDUCING THE WALL THICKNESS OF THE WORK. 